Treat ppc64 host as ppc

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

Makefile

diff --git a/Makefile b/Makefile
index 988dba8..2ff3e06 100644
--- a/Makefile
+++ b/Makefile
@@ -34,6 +34,7 @@
 	    -e s/arm.*/arm/ \
 	    -e s/sa110/arm/ \
 	    -e s/powerpc/ppc/ \
+	    -e s/ppc64/ppc/ \
 	    -e s/macppc/ppc/)
 
 HOSTOS := $(shell uname -s | tr '[:upper:]' '[:lower:]' | \